Biomaterial Database

Structural requirement of TAG-1 for retinal ganglion cell axons and myelin in the mouse optic nerve. 2008

Elli Chatzopoulou, and Andrés Miguez, and Maria Savvaki, and Grégoire Levasseur, and Aude Muzerelle, and Marie-Paule Muriel, and Olivier Goureau, and Kazutada Watanabe, and Laurence Goutebroze, and Patricia Gaspar, and Bernard Zalc, and Domna Karagogeos, and Jean-Léon Thomas

Institut National de la Santé et de la Recherche Médicale, Unité 711, Université Pierre et Marie Curie, Faculté de Médecine, Hôpital de la Salpêtrière, Institut Fédératif de Recherche 70, F-75013 Paris, France.

White matter axons organize into fascicles that grow over long distances and traverse very diverse environments. The molecular mechanisms preserving this structure of white matter axonal tracts are not well known. Here, we used the optic nerve as a model and investigated the role of TAG-1, a cell adhesion molecule expressed by retinal axons. TAG-1 was first expressed in the embryonic retinal ganglion cells (RGCs) and later in the postnatal myelin-forming cells in the optic nerve. We describe the consequences of genetic loss of Tag-1 on the developing and adult retinogeniculate tract. Tag-1-null embryos display anomalies in the caliber of RGC axons, associated with an abnormal organization of the astroglial network in the optic nerve. The contralateral projections in the lateral geniculate nucleus are expanded postnatally. In the adult, Tag-1-null mice show a loss of RGC axons, with persistent abnormalities of axonal caliber and additional cytoskeleton and myelination defects. Therefore, TAG-1 is an essential regulator of the structure of RGC axons and their surrounding glial cells in the optic nerve.

UI	MeSH Term	Description	Entries
D009186	Myelin Sheath	The lipid-rich sheath surrounding AXONS in both the CENTRAL NERVOUS SYSTEMS and PERIPHERAL NERVOUS SYSTEM. The myelin sheath is an electrical insulator and allows faster and more energetically efficient conduction of impulses. The sheath is formed by the cell membranes of glial cells (SCHWANN CELLS in the peripheral and OLIGODENDROGLIA in the central nervous system). Deterioration of the sheath in DEMYELINATING DISEASES is a serious clinical problem.	Myelin,Myelin Sheaths,Sheath, Myelin,Sheaths, Myelin
D009419	Nerve Tissue Proteins		Proteins, Nerve Tissue,Tissue Proteins, Nerve
D009457	Neuroglia	The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.	Bergmann Glia,Bergmann Glia Cells,Bergmann Glial Cells,Glia,Glia Cells,Satellite Glia,Satellite Glia Cells,Satellite Glial Cells,Glial Cells,Neuroglial Cells,Bergmann Glia Cell,Bergmann Glial Cell,Cell, Bergmann Glia,Cell, Bergmann Glial,Cell, Glia,Cell, Glial,Cell, Neuroglial,Cell, Satellite Glia,Cell, Satellite Glial,Glia Cell,Glia Cell, Bergmann,Glia Cell, Satellite,Glia, Bergmann,Glia, Satellite,Glial Cell,Glial Cell, Bergmann,Glial Cell, Satellite,Glias,Neuroglial Cell,Neuroglias,Satellite Glia Cell,Satellite Glial Cell,Satellite Glias
D009900	Optic Nerve	The 2nd cranial nerve which conveys visual information from the RETINA to the brain. The nerve carries the axons of the RETINAL GANGLION CELLS which sort at the OPTIC CHIASM and continue via the OPTIC TRACTS to the brain. The largest projection is to the lateral geniculate nuclei; other targets include the SUPERIOR COLLICULI and the SUPRACHIASMATIC NUCLEI. Though known as the second cranial nerve, it is considered part of the CENTRAL NERVOUS SYSTEM.	Cranial Nerve II,Second Cranial Nerve,Nervus Opticus,Cranial Nerve, Second,Cranial Nerves, Second,Nerve, Optic,Nerve, Second Cranial,Nerves, Optic,Nerves, Second Cranial,Optic Nerves,Second Cranial Nerves
D012160	Retina	The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.	Ora Serrata
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D004622	Embryo, Mammalian	The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.	Embryonic Structures, Mammalian,Mammalian Embryo,Mammalian Embryo Structures,Mammalian Embryonic Structures,Embryo Structure, Mammalian,Embryo Structures, Mammalian,Embryonic Structure, Mammalian,Embryos, Mammalian,Mammalian Embryo Structure,Mammalian Embryonic Structure,Mammalian Embryos,Structure, Mammalian Embryo,Structure, Mammalian Embryonic,Structures, Mammalian Embryo,Structures, Mammalian Embryonic
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000831	Animals, Newborn	Refers to animals in the period of time just after birth.	Animals, Neonatal,Animal, Neonatal,Animal, Newborn,Neonatal Animal,Neonatal Animals,Newborn Animal,Newborn Animals
D001369	Axons	Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.	Axon